Based on its review of the evidence, the USPSTF recommended that clinicians offer to prescribe risk-reducing medications such as tamoxifen, raloxifene or aromatase inhibitors to women who are at increased risk for breast cancer and who have a low risk for adverse medication effects. This is a "B" recommendation.
For women who are not at increased risk for breast cancer, the task force recommended against routine use of these medications -- a "D" recommendation.
In its final recommendation, the USPSTF emphasized that its guidance applies to women ages 35 and older who have no symptoms of breast cancer. It does not apply to women who have a current or previous breast cancer diagnosis.
"There are medications available that can help some women prevent breast cancer, but they are not for everyone," said task force member Michael Barry, M.D., in a news release. "For women who are at increased risk for breast cancer, these medications can be beneficial and reduce their risk."
The USPSTF noted that although medications such as tamoxifen, raloxifene or aromatase inhibitors provide at least a moderate benefit in reducing the risk for invasive estrogen receptor-positive breast cancer in at-risk women, these medications can also lead to serious harms. The likelihood of experiencing these harms depends on a woman's individual risk factors.
When deciding whether to offer medications, clinicians should carefully consider their patients' risk factors for breast cancer and balance those cancer risks against the potential harms from the drugs, some of which -- such as blood clots or other cancers -- may be serious or even life-threatening, the USPSTF said. The severity of these harms can vary by the specific medication and a woman's risk factors for these specific harms.
"We all want to find better ways to help prevent breast cancer, and it's important that clinicians talk with patients about their level of risk and carefully consider the best approach," said task force member Carol Mangione, M.D., M.S.P.H., in the release. "For women who are not at increased risk for breast cancer, these medications are not recommended because they may be more harmful than beneficial."
This final recommendation statement is consistent with the USPSTF's Jan. 15 draft recommendation and updates the task force's 2013 final recommendation, which the AAFP supported at that time. Specifically, the new recommendation statement added aromatase inhibitors as one of the medications clinicians can offer to women at increased risk for breast cancer.
The draft version of this recommendation statement was posted for public comment on the USPSTF website from Jan. 15 to Feb. 11.
In response to some commenters, the task force clarified that the recommendation statement doesn't list every scenario in which medications could be considered but instead provides information on risk factors clinicians could consider when assessing breast cancer risk in their patients.
Other commenters voiced concern that the task force was recommending risk-reducing medications at a lower five-year breast cancer risk threshold than it previously had.
"The USPSTF has not lowered its risk threshold for which it has found a net benefit with risk-reducing medications," the final recommendation statement said in response. "Instead, the current recommendation acknowledges the uncertainty around relying on a specific threshold calculated by risk assessment tools to identify women who may benefit from risk-reducing medications and offers an alternative approach to risk assessment of women, which includes clinician consideration of clinical risk factors."
Some commenters expressed consternation that the task force was no longer recommending "shared, informed decision-making."
"As with all of its recommendations, the USPSTF encourages clinicians to discuss with patients the risks and benefits of clinical preventive services in the context of each individual's personal health values and preferences when considering a service," the final recommendation noted in response, adding clarifying language to that effect in the Clinical Considerations section.
Lastly, per commenters' requests, the task force provided additional information on the selection of medications and menopausal status and clarified information on harms of aromatase inhibitors in the Clinical Considerations section.
The AAFP's Commission on Health of the Public and Science plans to review the USPSTF's final recommendation statement and evidence summary and will determine the Academy's stance on the recommendation.
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